Treasures

‘Dollond’ telescope research offers history lesson

 
 
 <span class="cutline_leadin">Looking good: </span>Telescope is marked ‘Dollond of London Day and Night.’
Looking good: Telescope is marked ‘Dollond of London Day and Night.’
Handout / MCT

McClatchy-Tribune

Q: My old telescope is marked “Dollond of London Day and Night.” It is about 45 inches long (50 inches extended) and has a wood and brass tripod that is about 5 feet high and very heavy. I believe it is from the early 1800s. Could you give me your opinion on age and value?

G.B., Bonita Springs, Fla.

A: To say that this wonderful telescope is a little out of our comfort zone is something of an understatement. This is the first letter we have ever received about an instrument such as this one, and despite the fact there is some missing vital information about the power and the size of the lens, we decided to do some research and see if we could not offer some insights into this tricky subject.

John Dollond FRS was an English optician who was born in June 1706 and died in November 1761. The “FRS” after his name stands for “Fellow of the Royal Society,” which was founded in 1660 and acts as the United Kingdom’s Academy of Sciences.

Dollond’s father was a Huguenot silk weaver and the son adopted his profession at first, but found time to give himself a classical education in Latin, Greek, mathematics, physics, anatomy and so forth. In February 1730, Dollard’s wife gave birth to their son Peter, who became a maker of optical instruments such as microscopes and telescopes. Peter started his business in 1750 and two years later, the elder Dollond (John) joined his son in this enterprise.

In 1758, John Dollond published Account of Some Experiences Concerning the Different Refrangibility of Light. This led Dollond to combine two different kinds of glass (“crown” and “flint”) into a lens that reduced the chromatic aberrations while looking at the stars or other distant objects.

It was called the “apochromatic doublet” lens, which allowed for refraction without color. Dollond did not invent this (that honor probably belongs to optician George Bass), but Dollond did patent it and exploited its commercial possibilities despite legal challenges from other opticians. John Dollard won the prestigious Copley Medal in 1758 and became “Optician to the King” shortly before his death in 1761.

Dollond telescopes are said to have sailed with Captain Cook on a voyage to observe the transit of Venus and to have been used by Lord Nelson. Peter Dollond died in 1821 but the company survived and in 1927 merged with Aitchison and Company to become Dollond and Aitchison.

There are some important things we do not know about G.B.’s telescope — we do not even know if it has its original box. We think this piece should have a 3 3/4-inch lens, and we did find an example of a Dollond telescope that looks exactly like the example in today’s question — right down to the star finder.

Unfortunately, the auction house that was selling it placed too high an estimate on it (in our opinion) and it did not sell. We have seen telescopes similar to this one described as “ship’s telescopes,” and discovered that circa 1840 Dollond telescopes of this size with their tripods, original box and star finders sell at auction in the $2,000 to $2,500 range.

Examples with a smaller lens (i.e., 2 1/2 inches) bring considerably less, in the $650 to $1,000 range. Insurance replacement value would be higher — perhaps as much as double.

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